This invention relates to anodes and has particular, but not exclusive, reference to anodes used in the electrowinning of cobalt.
In cobalt electrowinning, a layer of cobalt is deposited upon a cathode surface in an electrowinning cell. For reasons which are not fully understood, the cobalt layer has a high internal stress which can lead to the layer peeling away from the cathode surface and the cobalt layer coming into contact with the anode. These cathode deposits which peel off are known as "peelers."
A number of proposals have been made to prevent the peeling layer of cobalt coming into contact with the anode. For example, it has been proposed that a layer of canvas be inserted between the anode and the cathode. Unfortunately, however, the electrodeposit continues to grow on the peeler and this grows into the pores of the canvas. When the cathode is removed, the electrodeposit pulls the canvas and can rip or tear it completely clear of the anode. Similar objections apply to plastic meshes or grids.